There are dozens-like in any large city in EUR. Just use a site ;like booking.,com or hostelworld.

There are also chains that combine hoStel and Hotel-Meininger and AO-hostels (German chains, also in Wien). Note that a double in a cheapish normal hotel will often cost about same as 2 hoStelbeds-but then you miss of course the other facilities that hoStels tend to have.

What to do: do this: when arr, On the train tot here use the wifi and check if next leg will need REServ-do that then at counter. Then find the info-office (corner of the 2 large halls-just before the giant and quite good foodcourt), which also doubles as info-stack for many brochures on what to do in Wien-even some special ones for the gay/LHBTQB or what it is called today, fam+kids,  etc, They also sell the 24 hr tickets for local metro/tram/bus etc if you venture away from the raillines. Then find the best spot to eat this famous Sachertorte (that is not in that foodcourt)

Hi Rebecca,

Wombats is a popular place. There’s a bar but beside there are also enough non-party people and the bar (in the one near Naschmarkt) is on the ground floor. 
When I was staying there longer time ago (with school) it was reasonably clean and lots of people from around the world.
Jo&Joe Hostel seems to be also nice - they have nice rooftop with view over Vienna. But the rooftop can also be accessed by non-hostel guests.

What to do in Vienna: Schönbrunn, Belvedere, Prater, Stephansdom, Rathaus, Karlskirche, go to Kahlenberg (bus 38a from Heiligenstadt) and drink some wine (better to bring your own and sit somewhere in a wine yard, prices in the “Heurigen” places are ridiculously high… for tourists) while walking down to Nussdorf (tramline from there back to the center).
Go to Alte Donau for swimming, walk on the Donauinsel, visit the Museumsquartier and one of the museums there (Leopold museum.
Take the U2 to Krieau and spend some time in Viertel zwei and walk through the University of economics campus.
Visit the Zentralfriedhof (cemetery), many graves of famous ppl are there.

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